added langlinks() method to retrieve interlanguage links for a given article, as well as a convenience wrapper to retrieve the langlink for a specific language by language code
added langlinks() method to retrieve interlanguage links for a given article, as well as a convenience wrapper to retrieve the langlink for a specific language by language code

zloydadka/mediawiki-gateway,thenovices/mediawiki-gateway,blackwinter/mediawiki-gateway,jpatokal/mediawiki-gateway